It's hard to say for sure. While there's no proof that the Chattanooga Choo Choo ghost stories are true, the fact that they've been passed down could mean there was some sort of strange occurrence in the past that got exaggerated over time. Maybe there were some noises or odd feelings that people couldn't explain, and they turned it into a ghost story. But until we have some real evidence, it's best to take them with a grain of salt.
Well, Choo Choo Charlie's back story is quite interesting. He was born in a small town where the train was the main mode of transportation. His father worked at the train station, so Charlie was exposed to trains from a very young age. As he grew up, he spent most of his free time exploring the trains. He learned how to oil the parts, clean the engines, and even started to understand the complex mechanics behind them. His love for trains grew so much that he dedicated his life to them, and that's how he got the name Choo Choo Charlie.
The Chattanooga Choo Choo has a long and rich history. Regarding its ghost stories, it's possible that there are accounts of lovers who were separated at the station and their ghosts now linger there. Also, as the train was a major part of transportation in the past, there might be stories of lost children who got separated from their families on the train and are now said to haunt the Chattanooga Choo Choo premises. There could be unexplained cold spots or feelings of unease in certain areas that fuel these ghostly tales.
One idea could be to write a prequel fanfiction. Show how Charles came to be the menacing train he is. Maybe he was once an ordinary train that was experimented on by some mad scientist, which led to his transformation. This could explore his origin story in a detailed and exciting way.
Well, you can focus on creating unique characters. Don't just have the typical hero and villain. Maybe create a character with a special ability like being able to communicate with machines, which could be useful in dealing with Choo Choo Charles. This will make your story different from others.
The cultural context can be a factor too. A cologne with ingredients that are native to a particular region might tell a story of that place. For instance, a cologne with oud from the Middle East could tell a story of the rich, exotic culture there. The scent can transport you to that place and give you a sense of its traditions, people, and history.